Nvidia rooted by Linux graphics bug

Binary blob malaise

Updated Security researchers have published an exploit that highlights a long-standing security bug in Nvidia graphic drivers for Linux. Nvidia Driver For Linux v8774 and v8762 are subject to a buffer overflow bug that creates a means for hackers to inject hostile code as root. The bug might be exploited locally or remotely, providing malicious hackers are able to trick users into visiting a maliciously-constructed website.

Nvidia drivers for Solaris and FreeBSD, as well as earlier versions of Nvidia's closed-source Linux driver, are also likely to be vulnerable, according to security firm Rapid7, which published an advisory on the issue on Monday.

Nvidia supplied two graphic drivers for Linux - a closed source "binary blob" driver, which is subject to the vulnerability, and an open source driver, which is not subject to the bug. However, the open source driver lacks the acceleration features found in the closed source driver.

The flaw in the closed source driver stems from a security bug involving the accelerated rendering of text character data (glyphs) that might be used to crash the driver and write arbitrary code into memory that could be subsequently executed.

Rapid7 advises users to switch to the open source driver, included by default within X (X Window System), pending a security fix to its closed source code from Nvidia. News of the exploit is likely to spark debate over the use of binary-only blobs in otherwise open source operating systems.

According to Rapid7, there's been multiple public reports of the bug in Nvidia's closed source Linux driver that has been highlighted on the NVNews forum and elsewhere, dating back two years.

Nvidia publically acknowledged issues in July 2006 but is yet to publish a fix, prompting Rapid7 to release an advisory (complete with proof-of-concept code) as a way of highlighting its concerns.

Rapid7 reckons Nvidia's binary driver is subject to a number of other bugs which might be used to trigger crashes but not capable of being used to inject code, the more serious risk associated with the specific vulnerability it highlights. ®

Update

Reg readers informa us that Nvidia's latest beta driver for linux is (apparently) not affected by this exploit.